U.S. patent number 10,167,769 [Application Number 15/448,007] was granted by the patent office on 2019-01-01 for temperature control system for hybrid powertrain and method of operating a temperature control system.
This patent grant is currently assigned to Audi AG. The grantee listed for this patent is AUDI AG. Invention is credited to Michael Auerbach, Johannes Brunner, Ralf Kleisch, Andreas Oberting.
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United States Patent |
10,167,769 |
Auerbach , et al. |
January 1, 2019 |
**Please see images for:
( Certificate of Correction ) ** |
Temperature control system for hybrid powertrain and method of
operating a temperature control system
Abstract
A temperature control system for a hybrid powertrain includes a
first coolant circuit for temperature control of a first drive
device of the hybrid powertrain and a second coolant circuit for
temperature control of a second drive device. The second coolant
circuit has a first subcircuit, connected for heat transfer to the
second drive device, and a second subcircuit, connected at least
temporarily for heat transfer to an energy store of the second
drive device. The first and second subcircuits are operable
separately from one another. A coolant duct is connected to the
first drive device for heat transfer and is fluidly connected in a
first operating mode with the first coolant circuit in the absence
of a fluid communication with the second coolant circuit, and
fluidly connected in a second operating mode with the second
coolant circuit in the absence of a fluid communication with the
first coolant circuit.
Inventors: |
Auerbach; Michael (Ingolstadt,
DE), Brunner; Johannes (Neuburg an der Donau,
DE), Kleisch; Ralf (Asperg, DE), Oberting;
Andreas (Stuttgart, DE) |
Applicant: |
Name |
City |
State |
Country |
Type |
AUDI AG |
Ingolstadt |
N/A |
DE |
|
|
Assignee: |
Audi AG (Ingolstadt,
DE)
|
Family
ID: |
59700603 |
Appl.
No.: |
15/448,007 |
Filed: |
March 2, 2017 |
Prior Publication Data
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|
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Document
Identifier |
Publication Date |
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US 20170260894 A1 |
Sep 14, 2017 |
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Foreign Application Priority Data
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Mar 12, 2016 [DE] |
|
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10 2016 003 076 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F01P
7/165 (20130101); F01P 3/20 (20130101); F01P
9/06 (20130101); F01P 2050/24 (20130101) |
Current International
Class: |
F01P
3/20 (20060101); F01P 9/06 (20060101); F01P
7/16 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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102005047653 |
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Apr 2007 |
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DE |
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102007004979 |
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Aug 2008 |
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DE |
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102007005391 |
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Aug 2008 |
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DE |
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102010043576 |
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Mar 2012 |
|
DE |
|
2462904 |
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Mar 2010 |
|
GB |
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WO 2010/083198 |
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Jul 2010 |
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WO |
|
Primary Examiner: Tran; Long T
Attorney, Agent or Firm: Henry M. Feiereisen LLC
Claims
What is claimed is:
1. A temperature control system for a hybrid powertrain,
comprising: a first coolant circuit for controlling a temperature
of a first drive device of the hybrid powertrain; a second coolant
circuit for controlling a temperature of a second drive device of
the hybrid powertrain, said second coolant circuit having a first
subcircuit, connected in a heat-transmitting manner to a drive unit
of the second drive device, and a second subcircuit, connected at
least temporarily in a heat-transmitting manner to an enemy store
for the drive unit of the second drive device, said first and
second subcircuits being operable separately from one another; and
a coolant duct connected to the first drive device in a
heat-transmitting manner, said coolant duct being fluidly connected
in a first operating mode with the first coolant circuit in the
absence of a fluid communication with the second coolant circuit,
and fluidly connected in a second operating mode with the second
coolant circuit in the absence of a fluid communication with the
first coolant circuit, wherein the first coolant circuit includes
an air conditioning circuit and a cooling circuit configured for
operation independently from the air conditioning circuit, said
coolant duct being part of the cooling circuit at least
temporarily.
2. The temperature control system of claim 1, further comprising a
first valve device operably connected to the second coolant circuit
and configured to connect the second coolant circuit in a first
switching mode with a coolant cooler and to connect the second
coolant circuit in a second switching mode to the coolant duct.
3. The temperature control system of claim 1, further comprising a
heat source disposed in the first coolant circuit.
4. The temperature control system of claim 3, wherein the heat
source is an electric heat source.
5. The temperature control system of claim 1, further comprising a
heat source disposed in the air conditioning circuit.
6. The temperature control system of claim 5, wherein the heat
source is an electric heat source.
7. The temperature control system of claim 1, further comprising a
second valve device configured to fluidly connect the first and
second subcircuits with one another in a first switching mode and
to fluidly disconnect the first and second subcircuits from one
another in a second switching mode.
8. A temperature control system for a hybrid powertrain,
comprising: a first coolant circuit for controlling a temperature
of a first drive device of the hybrid powertrain; a second coolant
circuit for controlling a temperature of a second drive device of
the hybrid powertrain, said second coolant circuit having a first
subcircuit, connected in a heat-transmitting manner to a drive unit
of the second drive device, and a second subcircuit, connected at
least temporarily in a heat-transmitting manner to an energy store
for the drive unit of the second drive device, said first and
second subcircuits being operable separately from one another; and
a coolant duct connected to the first drive device in a
heat-transmitting manner, said coolant duct being fluidly connected
in a first operating mode with the first coolant circuit in the
absence of a fluid communication with the second coolant circuit,
and fluidly connected in a second operating mode with the second
coolant circuit in the absence of a fluid communication with the
first coolant circuit, wherein the second coolant circuit includes
a bypass line to bypass the energy store.
9. A temperature control system for a hybrid powertrain,
comprising: a first coolant circuit for controlling a temperature
of a first drive device of the hybrid powertrain; a second coolant
circuit for controlling a temperature of a second drive device of
the hybrid powertrain, said second coolant circuit having a first
subcircuit, connected in a heat-transmitting manner to a drive unit
of the second drive device, and a second subcircuit, connected at
least temporarily in a heat-transmitting manner to an energy store
for the drive unit of the second drive device, said first and
second subcircuits being operable separately from one another; a
coolant duct connected to the first drive device in a
heat-transmitting manner, said coolant duct being fluidly connected
in a first operating mode with the first coolant circuit in the
absence of a fluid communication with the second coolant circuit,
and fluidly connected in a second operating mode with the second
coolant circuit in the absence of a fluid communication with the
first coolant circuit, and a heat exchanger disposed in the second
coolant circuit and connected to a refrigerant circuit.
10. The temperature control system of claim 9, wherein the heat
exchanger is disposed in the second subcircuit of the second
coolant circuit.
11. A hybrid powertrain, comprising: a first drive device; a second
drive device; and a temperature control system which includes a
first coolant circuit for controlling a temperature of the first
drive device, a second coolant circuit for controlling a
temperature of the second drive device of the hybrid powertrain,
said second coolant circuit having a first subcircuit, connected in
a heat-transmitting manner to a drive unit of the second drive
device, and a second subcircuit, connected at least temporarily in
a heat-transmitting manner to an energy store for the drive unit of
the second drive device, said first and second subcircuits being
operable separately from one another, and a coolant duct connected
to the first drive device in a heat-transmitting manner, said
coolant duct being fluidly connected in a first operating mode with
the first coolant circuit in the absence of a fluid communication
with the second coolant circuit, and fluidly connected in a second
operating mode with the second coolant circuit in the absence of a
fluid communication with the first coolant circuit, wherein the
first coolant circuit includes an air conditioning circuit and a
cooling circuit configured for operation independently from the air
conditioning circuit, said coolant duct being part of the cooling
circuit at least temporarily.
12. A method of operating a temperature control system, comprising:
controlling a temperature of a first drive device of the hybrid
powertrain via a first coolant circuit; controlling a temperature
of a second drive device of the hybrid powertrain via a second
coolant circuit by connecting a first subcircuit of the second
coolant circuit in a heat-transmitting manner to a drive unit of
the second drive device, and by connecting a second subcircuit of
the second coolant circuit, at least temporarily, in a
heat-transmitting manner to an energy store for the drive unit of
the second drive device, with the first and second subcircuits
being operable separately from one another; connecting a coolant
duct to the first drive device in a heat-transmitting manner such
that the coolant duct is fluidly connected in a first operating
mode with the first coolant circuit in the absence of a fluid
communication with the second coolant circuit, and fluidly
connected in a second operating mode with the second coolant
circuit in the absence of a fluid communication with the first
coolant circuit, and operating a cooling circuit of the first
coolant circuit independently from an air conditioning circuit of
the first coolant circuit, with the coolant duct being part of the
cooling circuit at least temporarily.
13. A method of operating a temperature control system, comprising:
controlling a temperature of a first drive device of the hybrid
powertrain via a first coolant circuit; controlling a temperature
of a second drive device of the hybrid powertrain via a second
coolant circuit by connecting a first subcircuit of the second
coolant circuit in a heat-transmitting manner to a drive unit of
the second drive device, and by connecting a second subcircuit of
the second coolant circuit, at least temporarily, in a
heat-transmitting manner to an energy store for the drive unit of
the second drive device, with the first and second subcircuits
being operable separately from one another; connecting a coolant
duct to the first drive device in a heat-transmitting manner such
that the coolant duct is fluidly connected in a first operating
mode with the first coolant circuit in the absence of a fluid
communication with the second coolant circuit, and fluidly
connected in a second operating mode with the second coolant
circuit in the absence of a fluid communication with the first
coolant circuit; and providing a bypass line in the second coolant
circuit to bypass the energy store.
14. The method of claim 13, further comprising operably connecting
a first valve device to the second coolant circuit such as to
connect the second coolant circuit in a first switching mode with a
coolant cooler and to connect the second coolant circuit in a
second switching mode to the coolant duct.
15. The method of claim 13, further comprising disposing a heat
source in the first coolant circuit.
16. The method of claim 13, further comprising fluidly connecting
the first and second subcircuits with one another in a first
switching mode of a second valve device, and fluidly disconnecting
the first and second subcircuits from one another in a second
switching mode of the second valve device.
17. A method of operating a temperature control system, comprising:
controlling a temperature of a first drive device of the hybrid
powertrain via a first coolant circuit; controlling a temperature
of a second drive device of the hybrid powertrain via a second
coolant circuit by connecting a first subcircuit of the second
coolant circuit in a heat-transmitting manner to a drive unit of
the second drive device, and by connecting a second subcircuit of
the second coolant circuit, at least temporarily, in a
heat-transmitting manner to an energy store for the drive unit of
the second drive device, with the first and second subcircuits
being operable separately from one another; connecting a coolant
duct to the first drive device in a heat-transmitting manner such
that the coolant duct is fluidly connected in a first operating
mode with the first coolant circuit in the absence of a fluid
communication with the second coolant circuit, and fluidly
connected in a second operating mode with the second coolant
circuit in the absence of a fluid communication with the first
coolant circuit; and disposing a heat exchanger in the second
coolant circuit, and connecting the heat exchanger to a refrigerant
circuit.
18. The method of claim 17, wherein the heat exchanger is disposed
in the second subcircuit of the second coolant circuit.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
This application claims the priority of German Patent Application,
Serial No. 10 2016 008 076.3, filed Mar. 12, 2016, pursuant to 35
U.S.C. 119(a)-(d), the disclosure of which is incorporated herein
by reference in its entirety as if fully set forth herein.
BACKGROUND OF THE INVENTION
The present invention relates to a temperature control system for a
hybrid powertrain and method of operating a temperature control
system
The following discussion of related art is provided to assist the
reader in understanding the advantages of the invention, and is not
to be construed as an admission that this related art is prior art
to this invention.
A hybrid powertrain is used for example to power a motor vehicle by
using different types of drive devices to produce the necessary
torque. One drive device may be an internal combustion engine and
another drive device may be an electric machine. During operation,
the first and second drive devices generate heat. At the same time,
in order to run reliably and efficiently the first and second drive
devices should operate at a specific operating temperature or
temperature range. The use of cooling devices and heating elements
has been proposed to provide a temperature control. This is
accompanied by high energy consumption.
It would therefore be desirable and advantageous to obviate other
prior art shortcomings.
SUMMARY OF THE INVENTION
According to one aspect of the present invention, a temperature
control system for a hybrid powertrain includes a first coolant
circuit for controlling a temperature of a first drive device of
the hybrid powertrain, a second coolant circuit for controlling a
temperature of a second drive device of the hybrid powertrain, the
second coolant circuit having a first subcircuit, connected in a
heat-transmitting manner to a drive unit of the second drive
device, and a second subcircuit, connected at least temporarily in
a heat-transmitting manner to an energy store for the drive unit of
the second drive device, the first and second subcircuits being
operable separately from one another, and a coolant duct connected
to the first drive device in a heat-transmitting manner, the
coolant duct being fluidly connected in a first operating mode with
the first coolant circuit in the absence of a fluid communication
with the second coolant circuit, and fluidly connected in a second
operating mode with the second coolant circuit in the absence of a
fluid communication with the first coolant circuit.
The term "in a heat-transmitting manner" in relation to the coolant
duct is to be understood as relating to a coolant duct that can be
routed directly through the first drive device, e.g. in the form of
at least one coolant channel. When the first drive device is an
internal combustion engine, the coolant channel may be formed for
example in a casing of the internal combustion engine, in
particular in a cylinder crankcase of the internal combustion
engine.
It is also conceivable to route the coolant duct via a heat
exchanger which is in heat-transmitting relation with the first
drive device. The heat transfer connection between the heat
exchanger and the first drive device may be directly, i.e. the heat
exchanger may be placed or mounted directly on the first drive
device or be part thereof. The heat transfer connection may also be
established via a further medium, e.g. a coolant, a refrigerant, or
the like, that passes through the heat exchanger and is fed
subsequently to the first drive device.
The coolant duct can be selectively associated to the first coolant
circuit or the second coolant circuit. In the first operating mode,
the coolant duct forms part of the first coolant circuit and in the
second operating mode, the coolant duct forms part of the second
coolant circuit. Thus, the coolant duct is in fluid communication
with the first coolant circuit in the first operating mode and in
fluid communication with the second coolant circuit in the second
operating mode, while being disconnected from the respectively
other coolant circuit, i.e. in the first operating mode from the
second coolant circuit and in the second operating mode from the
first coolant circuit.
A temperature control system according to the present invention is
capable of being used in many ways, in particular during a warm-up
phase, for example. For example, heat produced by the first drive
device can be used to heat the second drive, in particular the
energy store, or heat produced by the second drive device can be
used to heat the first drive device and/or the energy store. For
example, when the first drive device heats up, at least one
component of the first drive device, e.g. a bearing, especially a
cylinder sleeve and/or a mounting point of the bearing, is
heated.
The operating mode of the temperature control system or of the
hybrid powertrain can be executed as a function of a temperature,
e.g. an outside temperature, i.e. ambient temperature, or a
temperature of the temperature control system or hybrid powertrain,
or advantageously also a temperature of the energy store. When the
temperature drops below a temperature threshold, there is no energy
or only insufficient energy that can be drawn from the energy store
in order to power the second drive device. Thus, it is necessary to
first warm up the energy store. For this purpose, heat generated by
the first drive device or internal combustion engine is used.
When the temperature is thus below the temperature threshold, the
first drive device is put into operation, while the second drive
device is disabled. In addition, the coolant duct is now associated
to the second coolant circuit, so that coolant in the second
coolant circuit is heated by heat generated by the first drive
device to thereby also warm up the second drive device and in
particular the energy store. Conversely, when the temperature
exceeds the temperature threshold, the second drive device can be
powered by electric energy drawn from the energy store.
When the temperature of the first drive device is smaller than its
operating temperature, provision may be made to use heat, produced
by the second drive device, for warming up the first drive device.
This is especially the case, when energy is drawn from the energy
store for powering the second drive device, i.e. when the
temperature exceeds the temperature threshold. The coolant duct is
also associated in this scenario to the second coolant circuit,
i.e. the second operating mode is executed. In the second operating
mode, the coolant duct is decoupled from a cooling device of the
temperature control system, especially a primary cooling device of
the temperature control system. Coolant streaming through the
coolant duct is thus prevented from flowing through the cooling
device. It is currently preferred that the operating temperature of
the first drive device exceeds the temperature threshold.
When the temperature of the energy store exceeds the temperature
threshold, while the temperature of the first drive device is
smaller than its operating temperature, the second drive device is
advantageously powered, whereas the first drive device is
disabled.
The first drive device is thus warmed up by heat generated by the
second drive device. Of course, the first drive device may also be
powered in addition. In this case, the first drive device is warmed
up by heat produced by the first drive device itself. Heat produced
by the second drive device may, however, be supplied for additional
heating.
When the temperature of the first drive device reaches operating
temperature or an operating temperature range, further heating of
the first drive device and the second drive device and its energy
store becomes unnecessary. Therefore, the first operating mode is
initiated in which the coolant duct is fluidly connected with the
first coolant circuit while being fluidly disconnected from the
second coolant circuit. During continued operation of the hybrid
powertrain, it can be additionally freely determined whether only
the first drive device, or only the second drive device, or both
the first and second drive devices is/are operated to provide the
torque for powering the motor vehicle.
According to another advantageous feature of the present invention,
a first valve device can be operably connected to the second
coolant circuit and configured to connect the second coolant
circuit in a first switching mode with a coolant cooler and to
connect the second coolant circuit in a second switching mode to
the coolant duct. The first valve device can include one or more
valves and is provided to couple or decouple the coolant duct and a
coolant cooler to and from the second coolant circuit.
Advantageously, the coolant duct and the coolant cooler can be
fluidly connected to or fluidly disconnected from the second
coolant circuit independently from one another. The valve may
involve, for example, a switching valve, mixing valve, slide valve,
or the like.
The coolant cooler can be fluidly connected to the second coolant
circuit in the first switching mode of the first valve device.
Provision may hereby be made for the coolant duct to be
disconnected from the second coolant circuit. Conversely, in the
second switching mode, the first valve device fluidly connects the
coolant duct to the second cooling circuit. Provision may also be
made in this case for the coolant cooler to be disconnected from
the second coolant circuit.
According to another advantageous feature of the present invention,
the first coolant circuit can include an air conditioning circuit
and a cooling circuit configured for operation independently from
the air conditioning circuit, the coolant duct being part of the
cooling circuit at least temporarily. The first coolant circuit is
thus composed of the air conditioning circuit and the cooling
circuit. The air conditioning circuit is provided to control the
temperature inside of the motor vehicle, such as a passenger
compartment. The cooling circuit can include, at least temporarily,
the coolant duct in the first operating mode and is provided to
dissipate heat from the first drive device or to feed heat to the
first drive device. As the air conditioning circuit and the cooling
circuit should be operated independently from one another, they
have each a separate coolant pump.
According to another advantageous feature of the present invention,
a heat source, e.g. electric heat source, can be disposed in the
first coolant circuit or in the air conditioning circuit. When
using heat, generated by the first drive device, for heating the
second drive device or the energy store, this heat is no longer
available to maintain the temperature inside of the motor vehicle.
Thus, heat has to be supplied to the first coolant circuit or air
conditioning circuit in another way. This can now be realized by
the provision of the heat source which may be part of an
engine-independent heating system of the motor vehicle.
As described above, the first coolant subcircuit of the second
coolant circuit is connected in a heat-transmitting manner with the
drive unit of the second drive device. Coolant in the first coolant
subcircuit can be supplied directly to the drive unit or to a heat
exchanger connected to the drive unit in a heat-transmitting
manner. The same applies for the second coolant subcircuit and the
energy store. The drive unit of the second drive device is
represented, for example, by an electric machine or electric
machine with power electronics. The first coolant subcircuit may
thus be connected with the electric machine or, as an alternative,
with both the electric machine and its power electronics in a
heat-transmitting manner.
The second coolant subcircuit can be connected to the energy store
in a heat-transmitting manner at least temporarily but also
permanently. When connected temporarily, a bypass line may be
provided to bypass the energy store. The energy store can include,
for example, battery cells or both battery cells and associated
power electronics, such as a charger. Thus, the second coolant
circuit is connected to the battery cells or both battery cells and
associated power electronics in a heat-transmitting manner.
The bypass line is provided to allow coolant, circulating in the
second coolant subcircuit, to circumvent the energy store.
Provision can thus be made for coolant to bypass the battery cells
of the energy store, whereas the power electronics of the energy
store can be permanently connected with the second coolant
subcircuit in a heat-transmitting manner.
According to another advantageous feature of the present invention,
a heat exchanger can be disposed in the second coolant circuit or
second coolant subcircuit and connected to a refrigerant circuit.
The heat exchanger may also be designated as "chiller". The
refrigerant circuit is provided to cool coolant flowing in the
second coolant circuit or second coolant subcircuit, regardless of
the ambient temperature. Thus, even at high ambient temperatures,
the refrigerant circuit enables to maintain the coolant, fed to the
energy store, at a sufficiently low temperature. Coolant
circulating in the second coolant circuit is coupled in a
heat-transmitting manner via the heat exchanger with a coolant in
the refrigerant circuit. For example, provision may be made to
relieve coolant in or at least in a region of the heat exchanger,
so that coolant of the second coolant circuit can be cooled
down.
The first and second coolant subcircuits can be operated separately
from one another. Thus, each of the first and second coolant
subcircuits includes a coolant pump. Coolant in the first coolant
subcircuit can thus circulate independently from the second coolant
subcircuit, and vice versa. As a result, heat generated by the
second drive device can be used to heat the first drive device,
without further warming up the energy store. The energy store may
actually be decoupled from the first drive device by operating the
first and second coolant subcircuits independently from one
another. It is, of course, also conceivable to simply shutdown one
of the first and second coolant subcircuits.
According to another advantageous feature of the present invention,
a second valve device can be provided to fluidly connect the first
and second subcircuits with one another in a first switching mode
and to fluidly disconnect the first and second subcircuits from one
another in a second switching mode. The second valve device may,
like the first valve device, include one or more valves, involving,
e.g., a switching valve, mixing valve, slide valve, or the like.
The fluid communication may be realized, for example, with an
adjustable mass flow rate. There is thus no need to permanently
maintain the second valve device in a fully open state. Rather, the
second valve device may only be partly open in the first switching
state or even temporarily fully closed, e.g. operated in a clocked
manner.
According to another aspect of the present invention, a hybrid
powertrain includes a first drive device, a second drive device,
and a temperature control system which includes a first coolant
circuit for controlling a temperature of the first drive device, a
second coolant circuit for controlling a temperature of the second
drive device of the hybrid powertrain, the second coolant circuit
having a first subcircuit, connected in a heat-transmitting manner
to a drive unit of the second drive device, and a second
subcircuit, connected at least temporarily in a heat-transmitting
manner to an energy store for the drive unit of the second drive
device, the first and second subcircuits being operable separately
from one another, and a coolant duct connected to the first drive
device in a heat-transmitting manner, the coolant duct being
fluidly connected in a first operating mode with the first coolant
circuit in the absence of a fluid communication with the second
coolant circuit, and fluidly connected in a second operating mode
with the second coolant circuit in the absence of a fluid
communication with the first coolant circuit.
According to another aspect of the present invention, a method of
operating a temperature control system includes controlling a
temperature of a first drive device of the hybrid powertrain via a
first coolant circuit, controlling a temperature of a second drive
device of the hybrid powertrain via a second coolant circuit by
connecting a first subcircuit of the second coolant circuit in a
heat-transmitting manner to a drive unit of the second drive
device, and by connecting a second subcircuit of the second coolant
circuit, at least temporarily, in a heat-transmitting manner to an
energy store for the drive unit of the second drive device, with
the first and second subcircuits being operable separately from one
another, and connecting a coolant duct to the first drive device in
a heat-transmitting manner such that the coolant duct is fluidly
connected in a first operating mode with the first coolant circuit
in the absence of a fluid communication with the second coolant
circuit, and fluidly connected in a second operating mode with the
second coolant circuit in the absence of a fluid communication with
the first coolant circuit.
BRIEF DESCRIPTION OF THE DRAWING
Other features and advantages of the present invention will be more
readily apparent upon reading the following description of
currently preferred exemplified embodiments of the invention with
reference to the accompanying drawing, in which the sole FIG. 1 is
a schematic illustration of a hybrid powertrain with a temperature
control system in accordance with the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The depicted embodiment is to be understood as illustrative of the
invention and not as limiting in any way. It should also be
understood that the FIGURE may not necessarily be to scale. In
certain instances, details which are not necessary for an
understanding of the present invention or which render other
details difficult to perceive may have been omitted.
Turning now to FIG. 1, there is shown a schematic illustration of a
hybrid powertrain in accordance with the present invention,
generally designated by reference numeral 1, for powering a motor
vehicle which is represented in FIG. 1 solely by the depiction of a
wheel 2 of a front axle and a wheel 3 of the rear axle. At least
the wheel 3 can be powered by the hybrid powertrain 1. The hybrid
powertrain 1 includes a transmission 4, e.g. a multi-speed
transmission, via which the wheel 3 is operably connected to a
first drive device 5 and a second drive device 6. The first drive
device 5 is an internal combustion engine, while the second drive
device 6 includes an electric machine 7, a power electronics 8
which is operably connected to the electric machine 7, and an
energy store 9 which includes a power electronics 10.
The hybrid powertrain 1 further includes a temperature control
system, generally designated by reference numeral 11. The
temperature control system 11 includes a first coolant circuit 12
and a second coolant circuit 13. The first coolant circuit 12 is
provided to control a temperature of the first drive device 5, and
the second coolant circuit 13 is provided to control a temperature
of the second drive device 6. The temperature control system 11
further includes a coolant duct 14 which can be fluidly connected
with the first coolant circuit 12 in a first operating mode and
with the second coolant circuit 13 in a second operating mode. In
either one of the first and second operating modes, the coolant
duct 14 is disconnected from the respectively other one of the
first and second coolant circuits 12, 13. The coolant duct 14
extends, for example, through the first drive device 5, i.e.
internal combustion engine, e.g. through a casing or through a
cylinder crankcase of the internal combustion engine.
One of the coolant circuits 12, 13, for example the first coolant
circuit 12, may be embodied as a high-temperature coolant circuit,
whereas the other one of the coolant circuits 12, 13, in this case
the second coolant circuit 13, may be embodied as a low-temperature
coolant circuit. Thus, during normal operation of the temperature
control system 1, involving a virtually stationary operation at
substantially constant coolant temperature, the temperature of
coolant in the first coolant circuit 12 is higher than the
temperature of coolant in the second coolant circuit 13.
Advantageously, both coolant circuits 12, 13 contain a same
coolant.
A first valve device 15 is provided to set the first operating mode
or the second operating mode. For sake of simplicity, only one
valve 16 of the valve device 15 is shown. The valve device 15
controls whether a coolant cooler 17, e.g. a low-temperature
coolant cooler, or the coolant duct 14 is connected to the second
coolant circuit 13, i.e. in a first switching state, the valve
device 15 connects the coolant cooler 17 with the second coolant
circuit 13, and in a second switching state, the valve device 15
connects the coolant duct 14 with the second coolant circuit
13.
The first coolant circuit 12 includes an air conditioning circuit
18 and a cooling circuit 19. The air conditioning circuit 18 is
provided to control the temperature inside the motor vehicle, i.e.
passenger cell of the motor vehicle, and includes an
air-conditioning heat exchanger 20, a heat source 21 and a coolant
pump 22. The coolant duct 14 forms at least temporarily part of the
cooling circuit 19 in the first operating mode. In the second
operating mode, in which the coolant duct 14 is fluidly connected
to the second coolant circuit 13, the coolant circuit 19 is
disconnected. The cooling circuit 19 includes a cooler 23, in
particular a primary cooler, which can be designated as
high-temperature cooler, and a coolant pump 24.
The first coolant circuit 12 includes at least two valves 25 and 26
by which the air conditioning circuit 18 and the cooling circuit 19
can be fluidly disconnected from one another. The valve 25 can be
embodied as a 3/2 directional control valve and the valve 26 can be
embodied as a 2/2 directional control valve. In a first switching
position of the valve 25, the air-conditioning heat exchanger 20 is
fluidly connected to the first drive device 5 for example, in
particular fluidly connected via the first drive device 5 to the
cooler 23. The coolant pump 24 conveys coolant of the first coolant
circuit 12 from the cooler 23 in the direction of the
air-conditioning heat exchanger 20. Coolant flows hereby through
the coolant pump 22 and/or the heat source 21 for example.
In a second switching position of the valve 25, the
air-conditioning heat exchanger 20 is advantageously fluidly
disconnected from the first drive device 5 and coolant exiting the
air-conditioning heat exchanger 20 is conveyed by the coolant pump
22 back to the air-conditioning heat exchanger 20 via a bypass line
27 and advantageously via the heat source 21. As a result, the air
conditioning circuit 18 can be operated in the second switching
position of the valve 24 independently from the cooling circuit
19.
When the valve 25 assumes the first switching position, the valve
26 assumes a first switching position, in which a coolant flow
through a bypass line 28 is blocked. The valve 26 assumes a second
switching position, when the valve 25 also assumes its second
switching position, to clear the bypass line 28. Coolant can now be
conveyed by the coolant pump 24 via the bypass line 28 to the
coolant duct 14 and from there to the cooler 23. Coolant can then
flow from the cooler 23 to the coolant pump 24. The cooling circuit
19 can also be operated independently, in particular independently
from the air conditioning circuit 18. This, however, is possible
only in the first operating mode in which the coolant duct 14 is
coupled to the first coolant circuit 12.
The second coolant circuit 13 includes a coolant subcircuit 29 and
a second coolant subcircuit 30. The first coolant subcircuit 29 is
connected in a heat-transmitting manner with the second drive
device 6, i.e. the electric machine and/or the power electronics 8
thereof. The valve device 15 controls hereby whether the coolant
cooler 17 or the coolant duct 14 is coupled to the first coolant
subcircuit 29. In the first operating mode, it is the coolant
cooler 17 that is fluidly connected to the first coolant subcircuit
29, whereas in the second operating mode, it is the coolant duct 14
that is fluidly connected to the first coolant subcircuit 29. A
coolant pump 31 is disposed in the first coolant subcircuit 29 in
addition to the electric machine 7 and/or the power electronics
8.
The second coolant subcircuit 30 is connected in a
heat-transmitting manner, at least temporarily, with the energy
store 9, and may also be connected in a heat-transmitting manner to
the power electronics 10, e.g. a charger of the energy store 9. A
coolant pump 32 is disposed in the second coolant subcircuit 30.
Coolant in the second coolant subcircuit 30 can bypass the energy
store 9 via a bypass line 33. A valve 34, e.g. a 3/2 directional
control valve, selectively closes or clears a coolant flow through
the bypass line 33. In a first switching position of the valve 34,
coolant of the second coolant subcircuit 30 flows through the
energy store 9, while the bypass line 33 is closed. In a second
switching position, coolant flows through the bypass line 33, but
not through the energy store 9.
A second valve device 35 is operably connected to the second
coolant circuit 13 and includes valves 36 and 37 to selectively
connect the coolant subcircuits 29, 30 with one another or fluidly
disconnect the coolant subcircuits 29, 30 from one another. For
example, in a first switching position of the valve 36, coolant of
the first coolant subcircuit 29 is conveyed by the coolant pump 31
directly to the power electronics 8 and/or the electric machine 7.
In a second switching position, coolant flows from the coolant pump
31 in the direction of the coolant pump 32, e.g. via a heat
exchanger 38 which is connected to a not shown refrigerant
circuit.
In a first switching position of the valve 37, a flow communication
is established between a downstream side of the coolant pump 32 and
the heat exchanger 38, in particular via the energy store 9 (in the
first switching position of the valve 34) and/or the power
electronics 10. In the second switching position of the valve 37,
the flow communication is blocked, so that instead a fluid
communication is established between the downstream side of the
coolant pump 32 and the power electronics 8 and/or the electric
machine 7, also advantageously via the energy store 9 and/or the
power electronics 10.
With the assistance of the valve devices 15, 35 and the valves 25,
26, 34, the first drive device 5 and the second drive device 6 can
be appropriately cooled and an appropriate heat transport between
the first and second drive devices 5, 6 is rendered possible. For
example, heat, generated by one of the drive devices 5, 6 can be
used to warm up the other one of the drive devices 5, 6 and/or
energy store 9.
While the invention has been illustrated and described in
connection with currently preferred embodiments shown and described
in detail, it is not intended to be limited to the details shown
since various modifications and structural changes may be made
without departing in any way from the spirit and scope of the
present invention. The embodiments were chosen and described in
order to explain the principles of the invention and practical
application to thereby enable a person skilled in the art to best
utilize the invention and various embodiments with various
modifications as are suited to the particular use contemplated.
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